EVALUATION OF AIRCREW OCCUPATIONAL NOISE EXPOSURE: RESULTS OF A LARGE PERSONAL DOSIMETRY SURVEY IN A MAJOR AIRLINE M. Klerlein, M.D – M.C. Bouton, M.D. Occupational Medicine, Air France ASMA 2014 annual scientific meeting, San Diego, 12 may 2014

WHY MEASURE NOISE EXPOSURE OF AIR CREW ? A LEGAL ISSUE… In 2012 France put back the age of retirement from 60 to 62 years Proven exposure to at least one of ten “hardness factors” allows leaving still at 60 One of these ten factors is “Exposure to more than a 8h continuous equivalent noise level of 85 dB(A)” SO… ARE AIRCREW EXPOSED TO MORE THAN 85 dB(A) ?

METHODS: 2 CONCEPTS Lex,8h (continuous equivalent noise level for 8 hours work): it is the noise dose a worker is exposed to if his shift lasted 8 hours Homogeneous Group of Exposure (H.G.E): a group of workers whose duties generate a similar noise exposure

PERSONAL NOISE DOSIMETRY Dosimeters are small devices that workers can wear during the whole shift They record the continuous equivalent noise level for small time period e.g. 1 minute, and log data during whole workshift

METHODS: THE ISO 9612:2009 STANDARD “Acoustics - Determination of occupational noise exposure - Engineering method “ This standard offers a statistical approach when dealing with large numbers of noise dosimetries It includes a scientific determination of the uncertainty of measurement, due either to the device or the sampling, at the scale of each H.G.E. A dedicated package has been used for analysis and calculation according to the ISO 9612:2009 Standard (DiagLexd, Gamba Acoustique, France)

EXAMPLE OF DIAGLEXD RESULTS Size of the H.G.E. Nb of dosimetries Uncertainties “True” noise dose “Legal” noise dose Distribution of noise dose results is tested for normality (Shapiro-Wilk test)

MEASUREMENTS 154 whole shift dosimetries recorded (whole shift : from briefing to hotel, and back) 1805 hours recorded 60 trips studied for the following H.G.E Pilots Airbus 320 family (318 to 321) Pilots Boeing 777 Pilots Boeing 747 Pilots Airbus 380 Pilots Airbus 330/340 Cabin crew Long Haul Cabin crew Medium & Short Haul

TRIPS MEASURED Dosimeters worn during the whole trip (2-4 legs) Dosimeters worn during the whole duty (outbound & inbound) but not during layover

RESULTS (1) H.G.E. H.G.E. size (Nb of workers) Nb of dosimetries Lex, 8h (dBA) Uncertainty Lex,8h corrected Cabin Crew Long Haul 9680 98 79.0 3.0 82.0 Cabin Crew Med. Short Haul 2980 19 80.7 3.1 83.8 Pilots 320 1447 8 80.3 83.1 Pilots 777 1277 11 79.8 Pilots 747 298 4 80.9 3.5 84.5 Pilots 330/340 522 77.5 80.5 Pilots 380 113 5 74.3 3.9 78.3

RESULTS (2) FOCUS ON SOME FLIGHT DECKS & CREW RESTS Noise dose for the time spend at the flight deck during flight, in dB(A) (34 recordings – mean duration 316 mn range 37-611) Noise dose of the time spend at the crew rest during flight, in dB(A) (106 recordings – mean duration 146 mn range 20-260)

CONCLUSIONS No H.G.E. exceed the 85 dBA threshold HOWEVER For medium and short haul flights, the A320 family flight deck is clearly too noisy (mean > 82 dBA) for the cognitive demand The noise level in crew rests is too high for a good sleep recovery for most aircrafts, except the A380.

Thank you for attention